Diffusion-fast color-forming developing agents

ABSTRACT

PHOTOGRAPHIC IMAGES ARE OBTAINED BY DEVELOPING AN IMAGEWISE EXPOSED LIGHT-SENSITIVE PHOTOGRAPHIC MATERIAL COMPRISING AT LEAST ONE SILVER HALIDE EMULSION LAYER, WHICH CONTAINS DIFFUSION FAST P-PHENYLENE DIAMINE TYPE DEVELOPING AGENTS IN THE FORMULA   1-(H2N-),2-R1,4-(X-(CH2)N-N(-R3)-),6-R2-BENZENE   WHEREIN R1 REPRESENTS HYDROGEN, ALKYL OR ALKOXY; R2 REPRESENTS HYDROGEN OR ALKYL; R3 REPRESENTS ALKYL FROM 8 TO 20 CARBON ATOMS; X REPRESENTS HYDROGEN, SULFO, CARBOXYL, HYDROXYL OR SULFONAMIDE, AND N PREPRESENTS 1 TO 4.   PREFERABLY ARE PRODUCED COLORED IMAGES, USING MATERIAL WHICH CONTAINS IN THE SAME LAYER AS THE DIFFUSION FAST DEVELOPER A COLOR-FORMING COUPLER OR A DYE-GIVING COMPOUND WHICH ON REACTION WITH DEVELOPED OXIDATION PRODUCTS RELEASES A DIFFUSIBLE DYE. THE DEVELOPMENT IS PREFERABLY CARRIED OUT IN THE PRESENCE OF A PYRAZOLIDONE-3 COMPOUND.

United States Patent many No Drawing. Filed June 5, 1970, Ser. No. 43,939 Claims priority, application Germany, June 19, 1969, P 19 31 057.7 Int. Cl. G03c 7/00, 1/06, N48

US. Cl. 96-55 4 Claims ABSTRACT OF THE DISCLOSURE Photographic images are obtained by developing an imagewise exposed light-sensitive photographic material comprising at least one silver halide emulsion layer, which contains diffusion fast p-phenylene diamine type developing agents in the formula wherein R represents hydrogen, alkyl or alkoxy;

R represents hydrogen or alkyl;

R represents alkyl from 8 to 20 carbon atoms;

X represents hydrogen, sulfo, carboxyl, hydroxyl or sulfonamide, and

n represents 1 to 4.

Preferably are produced colored images, using material which contains in the same layer as the diflusion fast developer a color-forming coupler or a dye-giving compound which on reaction with developed oxidation products releases a ditfusible dye. The development is preferably carried out in the presence of a pyrazolidone-3 compound.

DIFFUSION-FAST COLOR-FORMING DEVELOPING AGENTS The invention relates to a photographic material which contains a developer, and more particularly the invention relates to a photographic material comprising at least one silver halide emulsion layer which contains a developer of the p-phenylene diamine type which is incorporated in a form which is fast to diffusion.

Numerous photographic developing agents, both blackand-white developers and color-forming developers are already known. Because of the large variety of requirements of photographic reproduction processes, however, there is a need for new photographic developers.

Photographic developing agents are relatively sensitive to oxidation, both when they are present in the form of an aqueous solution in the developer bath, and when they are present in the photographic layer. Their activity deteriorates considerably on prolonged storage in air. Moreover, the stability on storage of silver halide emulsion layers which contain photographic developing agents is unsatisfactory because such layers readily tend to fog. It has, therefore already been proposed to incorporate socalled masked developing agents in emulsion layers. These masked developers are characterized in that the photographically active groups, e.g. phenolic hydroxyl groups or aromatic amino groups are substituted with groups, e.g. by acylation or esterification, which remove the photographic activity of the compounds and hence also their 3,705,035 Patented Dec. 5, 1972 ice susceptibility to oxidation. At alkaline pH values, these substituents are split off so that the photographic activity can be completely restored. One disadvantage of these compounds is that the liberation of the developing agents requires a certain time, so that development can take place only after considerable delay. This results in insufiiciently developed photographic images.

It is the object of the invention to produce a developing agent which can be incorporated in silver halide emulsion layers without impairing the photographic and mechanical properties and which has sufiicient activity as a developer..

A photographic light-sensitive material comprising at least one silver halide emulsion layer containing a pphenylene diamine type developing agent and optionally containing a color-forming coupler or a dye-giving compound has now been found wherein the p-phenylene diamine type developing agent incorporated in the silver halide emulsion layer or in a hydrophilic colloid layer adjacent thereto is resistant to dififusion and has the formula:

wherein R represents a hydrogen atom, an alkyl group, preferably a short chained alkyl group containing up to 5 carbon atoms, in particularly methyl or ethyl, or an alkoxy group, particularly a short chained alkoxy group containing up to 3 carbon atoms, such as methoxy or eth- Y;

'R represents a hydrogen atom or an alkyl group, preferably a short chained alkyl group containing up to 5 carbon atoms, in particular methyl or ethyl;

R represents a long chained alkyl radical containing from 8 to 20 carbon atoms, preferably from 12 to 18 carbon atoms, for example dodecyl, heptadecyl or octadecyl;

X represents a hydrogen atom or a sulto, carboxyl, hy-

droxyl or sulfonamide group, in which the amide group may be substituted with alkyl radicals, in particular short chained alkyl radicals such as methyl or ethyl, and

n represents an integer from 1 to 4.

The following are examples of suitable compounds: 1 C12H25 C nHis CHz-CHz-NHS O CH;

HZNQ-N a The preparation of developer 1 is described below. The other developers are prepared in an analogous manner.

43.5 parts of 4-nitroso-N-dodecyl-N-w-sulfopropyl aniline are dissolved in 185 parts of methanol and after the addition of Raney nickel the solution is hydrogenated at 60 C. under a hydrogen pressure of 100 excess atmospheres. A concentrated methanolic solution of 35 parts of naphthalene-1.5-disulfonic acid is added to the filtered solution and the mixture is stirred under nitrogen for one hour at 15 C., the precipitate of developer salt is removed by suction filtration and the residue is washed with methanol and dried. Yield: 62 parts of developer salt.

4-nitroso-N-dodecyl-N-w-sulfopropyl aniline is prepared as follows:

26 parts of N-dodecylaniline are mixed with 12.8 parts of propanesultone in 26 parts of toluene and boiled under reflux for 1 /2 hours. After removal of the solvent by distillation, the residue is dissolved in a mixture of 51 parts of water with 14.3 parts of concentrated sulfuric acid, and a solution of 7 parts of sodium nitrite in 12.5 parts of water is added dropwise within 15 minutes to the mixture which has been cooled to C. The mixture is then stirred for 30 minutes at 0 C., diluted with 270 parts of water and adjusted to pH 9 with concentrated sodium hydroxide solution. The nitroso compound is precipitated by the addition of parts of sodium chloride and is removed by suction filtration and washed with 2.5% sodium chloride solution. The compound is obtained pure by recrystallization from 500 parts of 2.5% sodium chloride solution. After drying, a yield of 25 parts of nitroso compound is obtained.

N-dodecylaniline is prepared as follows:

37.2 parts of aniline are mixed with 24.8 parts of l-bromododecane and boiled under reflux for one hour. After cooling, 20 parts of 20% sodium hydroxide are added, the aqueous phase is separated off and the oil is washed with water, dried over sodium sulfate and distilled. N-dodecylaniline distills over at 0.08 mm. Hg at 150.5 to l51.5 C. in a yield of 19.5 parts.

On their own, the diffusion fast p-phenylene diamine derivatives to be used according to the invention have little or no effect as photographic developers even in an alkaline medium. It has now surprisingly been found that in the presence of small quantities of developers of the pyrozolidone-3 type they are extremely active developers. They then have at least the same activity as the conventionally used color-forming developers of the phenylene diamine series.

tPyrazolidone-3 derivatives of the following formula are suitable for use in combination with the p-phenylene diamine type developing agents to be used according to the invention:

wherein R represents a hydrogen atom;

R R R and R each represents a hydrogen atom, an allayl or aryl group or a substituted alkyl or aryl group, an

R represents a hydrogen atom or an alkyl or aryl group which may be substituted, for example with lower alkyl or alkoxy groups or halogen atoms.

The compounds shown in the following table have been found suitable:

I-phenyl-B-pyrazolidone,

l-m-tolyl- 3 -pyr azolidone,

1- p-tolyl-3 -pyrazolidone, 1-phenyl-4-methyl-3- pyrazoli done, 1-phenyl-5-methyl-3-pyrazolidone, 1-phenyl-4,4-bis- (hydroxymethyl -3-pyrazolidone 1,4dimethyl-3-pyrazolidone, 4-methyl-3-pyrazolidone, 4,4-dimethyl-3-pyrazolidone, l-phenyl-4,4-dimethyl-3 -pyrazo1idone,

l- 3-chlorophenyl -4-methyl-3-pyrazolidone, l- 4-chlorophenyl -4-rnethyl-3 -pyrazolidone, l- 3-chlorophenyl -3-pyrazolidone,

1- 4-chlorophenyl -3-pyrazolidone,

l- 4-tolyl-4-methyl-3-pyrazolidone,

l- 2-tolyl -4-methyl-3-pyrazolidone,

1- 4-tolyl -3-pyrazolidone,

l- 3-tolyl -3-pyrazolidone,

l-( 3-tolyl -4,4-dimethyl-3-pyrazolidone,

1- Z-trifluoroethyl) -4,4-dimethyl-3-pyrazo1idone, 5 -methyl-3 -pyrazolido me.

The p-phenylene diamine type developing agents to be used according to the invention are added to the casting solutions, for example for the silver halide emulsion layers or for other hydrophilic colloid layers in the form of solutions e.g. in water or in organic solvents which are miscible with water such as short chained aliphatic alcohols or dimethyl formamide, preferably shortly before casting. The concentration of the developers in the layer may vary within wide limits. It depends on the effect required and on the nature of the reproduction process and the type of silver halide. Quantities of between 1 and 30 g./mol of silver halide are generally sufficient. The optimum quantity can be found by a few simple laboratory tests. Concentrations of between 3 and 20 g./rnol of silver halide are preferred.

The phenylene diamine derivatives to be used according to the invention may be used in any silver halide emulsions. Silver chloride, silver bromide or mixtures thereof optionally containing a small amount of silver iodide e.g. of up to 10 mols percent are suitable for use as silver halide.

The silver halides may be dispersed in the usual hydrophilic and water-permeable binders such as proteins, particularly gelatin, or cellulose derivatives such as carboxymethylcellulose or hydroxyethyl cellulose, either alone or in admixture-with gelatin, or synthetic binders such as polyvinyl alcohol, partially saponified polyvinyl acetate and polyvinyl pyrrolidone. These compounds can also be used as binders in non-light sensitive interlayers which do not contain silver halide.

The phenylene diamine developers to be used according to the invention are color-forming developers. They are, therefore, preferably used for color photographic processes. For this purpose they are particularly suitable for silver halide emulsions which contain the usual colorforming couplers which are described e.g. in the publication by W. P'elz in Mitteilungen aus den Forschungslaboratorien der Agfa, volume 3, publishers Springer- Verlag, Berlin, 1961, pages 111-175.

These color-forming couplers may be either colorless or colored. They react with the oxidation products of the color-forming developers, which are produced on development of the exposed silver halide, to form the image dye.

The p phenylene diamine type developing agents to be used according to the invention are particularly suitable for color photographic diffusion transfer processes. The silver halide emulsion layer of the light-sensitive photographic materials for this process contains compounds which are also capable of reacting with the oxidation products of the p-phenylene diamine type developing agents. In this reaction, the dyes are split off and are then diffu'sible and can be transferred to an image receiv ing layer. Processes of this type are described in US. Patent No. 3,227,550.

According to one particularly preferred embodiment of the present invention, the p-phenylene diamine type developing agents are used in silver halide emulsions containing dye-giving compounds of the type described in U.S. Patent No. 3,628,952.

These dye-giving compounds are capable of reacting with the oxidation products of the developing agents to release a dififusible dye which subsequently can be transferred to a receiving layer.

As mentioned above the p-phenylene diamine type developing agents according to the present invention can also be incorporated in a hydrophilic colloid layer which is adjacent to the silver halide emulsion layer. If, however, the developing agents are to react in their oxidized form with color-forming couplers or dye-giving compounds, these latter mentioned reaction components should be incorporated in the same layer as also the p-phenylene diamine type developing agents.

The diffusion fast phenylene diamine developers of the present type may also be used in spectrally sensitized emulsions, e.g. those which have been sensitized with the usual monomethine or polymethine dyes such as cyanines, hemicyanines, streptocyanines, merocyanines, oxonoles, hemioxonoles, styryl dyes or other methine dyes which also contain three or more nuclei, for example, rhodacyanines or neocyanines. Such sensitizers are described by F. M. Hamer in the Work The Cyanine Dyes and Re lated Compounds (1964), Interscience Publishers, John Wiley and Sons.

The emulsions may also contain chemical sensitizers e.g. reducing agents such as stannous salts, polyamines such as diethylene triamine and sulfur compounds as described in US. Patent No. 1,574,944. The emulsions may also contain salts of noble metals such as ruthenium, rhodium, palladium, iridium, platinum or gold for chemical sensitization, as described in the article by R. Koslowsky, Z. Wiss. Phot. 46, 65 to 72 (1951). The emulsions may also contain compounds of the polyalkylene oxide type, e.g. polyethylene oxide and derivatives thereof, as chemical sensitizers.

The emulsions may also contain the usual stabilizers.

The photographic materials according to the invention are in principle processed in a known manner. In photographic color negative processes, exposure is immediately followed by color-forming development. The color-forming development bath used is a so-called activator solution which contains mainly alkalies and according to a preferred embodiment contains a pyrazolidone-3-derivative, in particular l-phenylpyrazolidone. The pyrazolidone-3-compound may, however, be partly or entirely contained in the photographic material, for example, in the light-sensitive silver halide emulsion layer or in an adjacent hydrophilic colloid layer. After the color-forming development processing is carried out in the usual manner. Bleaching and fixing or combined bleach fixing is carried out with baths of the usual composition.

The photographic material according to the invention may also be used for the production of positive colored images by color photographic reversal processes, for example, by the silver salt diffusion process as described in the US. Patent No. 2,673,800. According to such a process, for example, the diffusion-fast developing agents are incorporated in a hydrophilic colloid layer together with color-forming couplers or together with the dye-giving compounds of the U.S. Patent No. 3,628,952 and together with nuclei for the physical development. Onto this layer there is coated a light-sensitive silver halide emulsion layer. By processing with an activator bath containing a silver salt solvent and a 3-pyrazolidone compound a positive color image is obtained.

The activator baths preferably have a pH of from 8 to 14.

The pyrazolidone content is e.g. from 10 mg. to 1 g. per liter. Other conventional additives may also be present, e.g. stabilizing agents such as alkali metal bromides.

The following examples illustrate the invention:

EXAMPLE 1 Preparation of the photographic material The following layers are applied to a layer support of baryta-coated paper g./m.

1) A silver bromide gelatin emulsion layer which contains in 500 g. of emulsion, 6 g. of the coupler of the formula l -SO3H 6 g. of compound 1, 0.3 g. of saponine and 0.25 g. of N,N, N-trisacryloylhexahydrotriazine as hardener.

(2) A protective layer of a 2.5% gelatin solution. Processing: The material is exposed in a conventional sensitometer behind a grey wedge and is then processed as follows:

(a) Development: 4 minutes in a solution of 0.1 g. of

1-phenyl-3-pyrazolidone, 3 g. of anhydrous sodium sulfite, 25 g. of anhydrous soda, 1 g. of KBr, water up to 1000 ml.

(b) Washing: lminute.

(c) Bleach fixing: in a bath of 26 g. of tetrasodium ethylene diaminotetraacetate, 24 g. of anhydrous soda, 15 g. of ferric chloride, 13 g. of sodium anhydrous sulfite, 200 g. of sodium thiosulfate, water up to 1000 ml.

(d) Washing: 5 minutes.

A magenta wedge which is opposite in gradation to the original and has low fog and high color saturation is obtained.

EXAMPLE 2 Application in the photographic dye diffusion transfer process Light-sensitive multilayer photographic material: The following layers are applied in the given sequence to a layer support of white pigmented cellulose triacetate:

(1) A silver iodobromide gelatin emulsion containing per kg. 63.5 g. of silver bromide and 3.3 g. of silver iodide. The emulsion also contains the following additives per kg.:

12 mg. of a red-sensitizer of the formula:

(described in Example 11 of the German Auslegeschrift 1,213,240.)

0.4 g. of saponin, 5 g. of a compound of the following formula which on reaction with the oxidation product 8 of the color-forming developer splits off a dilfusible (described as dye-giving compound N0. 32 in US. cyan dye: Pat. No. 3,628,952);

OH OCH@ 11 N=N N=N s -Cw aa S03H ()CHa HOaS SOz-NH-N=C\ z)z S0311 (described as dye-giving compound 2 in US. Pat. No. 7 g. of compound 1; 3,628,952); 12 g. of compound 1, and 0.5 g. of N,N, 0.3 g. of saponin as wetting agent and N"-trisacryloylhexahydrotriazine as hardener; silver ap- 15 0.3 g. of N,N,N"-trisacryloylhexahydrotriazine as hardplication 0.9- g. per m ener; (2) An intermediate layer of a 2% aqueous gelatin silver application 1 g./m. solution.

Image receiving material.A 10% aqueous gelatin 63 i g g g g i i 20 solution which contains 20 g. of polyvinyl pyridine per kg.

o ver 5 1? 51 ver 10 1 e an is applied to a layer support of white pigmented cellulose g. of gelatin. The following additives are also added to triacetate The thickness of the dried layer is from 5 the casting solution for the emulsion layer: to 8% mg. of a greemsensitizer of the formula: Processing.-The exposed photographic material and the image receiving material are dipped for seconds /s\ CH3 into a developer bath of the following composition:

C=CH 0.5 g. of potassium bromide HO 3 0.1 g. of l-phenylpyrazolidone-3 and a 20 g. of potassium carbonate Ha v N 30 water up to 1000 ml.

$2115 The pH of the bath is adjusted to 11. The developer (desccnbed as dye No. 9 1n the German Ausle-geschnft bath had a temperature of .0

1,177,481); After removal from the developer, the layers of the 6 gmp followmg formula Whlch on light-sensitive material and the gelatin layer of the image reaCtlOn Wlt the OXIdatIOH Product Of the receiving material are brought into contact with each ing developer splits off a dilfusible magenta dye: other and kept in close contact for 5 minutes. They are Has ia L C=NHNS0z-CONH- N 1 1 S0311 N l lHm HQ OaH CHaSOzHN (described as dye-giving compound 1 No. 11 in US. then separated and the image receiving material is Pat. No. 3,628,952); thoroughly washed for about 3 minutes and then dried. 12 of compound 1; A positive image which has a density maximum of 0.5 g. of saponin as Wetting agent and about 2 is obtained. The colored image has very clear 0.5 g. of N,N',N"-trisacryloylhexahydrotriazine as hardcolors and excellent bnnlanceener. The silver application is 1 g. per 111. EXAMPLE 3 (4) An intermediate layer of a 2% aqueous gelatin Solution. Llght-sensitlve multilayer material (5) An unsensitized silver halide gelatin emulsion which contains per kg. 63.5 g. of silver bromide, 3.3 g. of silver iodide and g. of gelatin. The following additives are also added per 500 g. of the above emulsion:

The following layers are applied in the given sequence to a layer support of White pigmented cellulose triacetate:

(1) A 5% aqueous gelatin solution which contains per 5 g. of a compound of the following formula which on r kg. 20 g. of trimethyloctadecyl ammonium sulfate, 0.4 g. reaction with the oxidation product of the color-formof saponine and 4 ml. of a 5% aqueous formaldehyde ing developer splits off a diffusible yellow dye: solution. The thickness of the layer is 6n.

(2) A aqueous gelatin solution which contains per (described as dye-giving compound No. 12 in the U.S. kg. 50 g. of sodium alginate. The thickness of the layer Pat. No. 3,628,952), is 1.5a. 3.5 g. of compound 6,

(3) A silver halide gelatin' emulsion which contains 0.2 g. of saponine and per kg. 63.5 g. of silver bromide, 3.3 g. of silver iodide 0.3 g. of N,N,N"-trisacryloylhexahydrotriazine as hardand 80 g. of gelatin. In addition, the following substances 5 ener; are added per kg. to the casting solution for this layer: silver application about 0.8 g. per m of the green Sensmzer of Example 6 of a (8) A protective layer of a 2% aqueous gelatin solucompound of the following formula which on reaction with the oxidation product of the color-forming devel- 10 oper splits off a diffusible magenta dye:

/S NH2 es n C=NHNS O2-C ONHN=N LY N S0311 HO- 03 80:11

03H (described as dye-giving compound No. 36 in U.S. Pat. Processing.The above material is exposed behind a No. 3,628,952). colored negative and then immersed for 30 seconds in a 65 of compound 6; developer bath of the following composition: 0.3 g. of saponine as wetting agent and 0.8 g. of potassium bromide,

0.3 g. of N,N',N"-trisacryloylhexahydrotriazine as hardg. of potassium carbonate,

0.1 g. of 1-phenylpyrazolidone-3 and ener. silver application 0.9 g. per m 1 g. of hydroxyethylcellulose water up to 1000 ml.; (4) An intermediate layer of a 2% gelatin solution. PH adjusted to -(5) A silver halide gelatin emulsion layer of the com- 30 position indicated in Example 2 which contains per kg. the following substances:

The material is removed from the developer bath and after about 2 minutes it is treated with a strong jet of water. The emulsion layers are thus dissolved away.

12 mg. of red sensitizer according to Example 2, A colored positive image of the original is produced 6 g. of the compound used in the red-sensitive layer of F in the gelatin layer which is arranged immediately on Example 2 which on reaction with the oxidation prodthe support layer. The colored image has extremely briluct of a color-forming developer splits off a diffusible liant and very saturated colors. cyan dye, 6.5 g. of compound 6; EXAMPLE 4 0.4 g. of saponine as wetting agent and A 10% aqueous gelatin solution containing per kg. 20 0.5 g. of N,N',N"-trisacryloylhexahydratriazine as hardg. of a compound of the following formula which on ren r; action with the oxidation product of the color-forming silver application 0.9 g. per 111. developer splits off a diffusible magenta dye:

d m s 0H NH H25 1z I NNHSO2C O-N H-N=N- Br \N Hols SOHH (6) An intermediate layer of a 2% gelatin solution. (described as dye-giving compound No. 34 in the U.S. (7) An unsensitized silver bromide gelatin emulsion of Pa NO- 3,628,952), 12 g. of compound 7 and 15 mg. of the type indicated in Example 2 which contain the 1- silver sulfide, is coated on to a layer support of cellulose lowing additives per 500 g. of emulsion: triacetate; layer thickness 1.8a. Onto this layer is coated a green-sensitized silver bromoiodide emulsion as de- 5 g. of a compound of the following formula which on scribed in Example 2, which however, did not contain a reaction with the oxidation product of a color-forming dye-giving compound and a developing agent; silver coatdeveloper splits ofi a yellow dye: ing 1.6 g./m.

S OCzHs SOaH mHxs I C=NHNS O Q-C O-NH N: N 1'...

1 1 The material is exposed behind a green step wedge and dipped for 40 seconds into an activator bath of the following composition:

0.5 g. of potassium bromide 0.1 g. of l-phenyl-3-pyrazolidone 0.5 g. of sodium thiosulfate 20 g. of potassium carbonate water up to 1000 ml.

pH adjusted to 11.6.

Then the material is brought for 3 minutes into intimate contact with an image-receiving material as described in Example 2. After separation a positive magenta wedge is obtained having a maximum density of 1.45 and a minimum density of 0.18.

We claim:

1. In a process for the production of color photographic images by developing in the presence of a p-phenylenediamine type developing agent an imagewise exposed lightsensitive photographic material containing in at least one silver halide emulsion layer or in a hydrophilic colloid layer adjacent thereto a color-forming coupler resistant to dilfusion and capable of reacting with the oxidation products of said p-phenylene diamine type developing agent to form a dye, or containing in one of said layers a dye-giving compound resistant to diffusion and capable of reacting with the oxidation products of said p-phenylene type developing agent to release a dilfusible dye, the steps of incorporating in the same layer containing the color-forming coupler or the dye-giving compound a diffusion fast p-phenylenediamine type developing agent corresponding to the formula wherein R represents hydrogen, alkyl containing up to carbon atoms, or alkoxy containing up to 3 carbon atoms; R represents hydrogen or alkyl containing up to 5 carbon atoms;

12 R represents alkyl containing from 8 to 20 carbon atoms; X represents hydrogen or a sulfo, carboxyl, hydroxyl or sulfonamide group, and n represents an integer from 1 to 4; and developing the material with an alkaline bath in the presence of a pyrazolidone-S developing agent.

2. The process of claim 1 wherein the dye formed by reaction of the dilfusion fast p-phenylenediamine type developing agent with the color-forming coupler is resistant to diffusion and forms a dye image.

3. The process of claim 1 wherein the dye formed by reaction of the diffusion fast p-phenylenediamine type developing agent with the color forming coupler or with the dye giving compound is dilfusible and is transferred to an image-receiving layer to form a colored transfer image.

4. The process of claim 1, in which the pyrazolidone-3 developing agent has the formula:

R represents hydrogen, and R R R R and R represent hydrogen, alkyl or aryl.

References Cited UNITED STATES PATENTS 2,940,849 6/ 1960 Whitmore 96-3 3,178,286 4/1965 Willems 96-56 3,278,306 10/1966 Greenhalgh 96-55 3,482,971 12/ 1969 Bloom 96-3 3,498,785 3/ 1970 Bloom 963 3,549,370 12/1970 Sykes 96-55 J. TRAVIS BROWN, Primary Examiner I. R. HIGHTOWER, Assistant Examiner US. Cl. X.R. 96-3,

3 UNlTE-D STATES PATENT mums I CER'HHEAE @F QQRRECTEU 397 53 35 Dated Defiemhpr I97? Patent No" Hans Ve'ifcer et al Inventor(s) It is certified that error appears in the above=idenftified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, compound N00 5, the left-hand side of the formula should read as follows:

3 Column 3, line 60, the formula should read as follows:

9% RA u 1 Column '7, line .51, (first line after the formula), delete "1" after compound.

Column 9, bottom formula, the right hand side of, the formula should read as follows:

CLO-=CH=CH-COOH Patent Now 3,705,035 Dated December 5, 1972 Inventors Hans Vetter et al Page 2 Column 11, claim 1, line 27, delete "ene" and insert enediamine Column 12, the formula of claim should read as follows:

Signed and sealed this 20th day of November 19736 (SEAL) Attest:

EDWARD M.FLETCHER JRO D. TEGTME ER Attesting Officer Acting Coissioner of Patents 

